Made because coronavirus sucks and I'm very bored. Open up issues on the github repo if something breaks.
The distance between the country you guessed and the actual country is calculated with a modified version of the Haversine forumla that gives a maximum value of 1. That value is fed into a steep exponentially decreasing function (y = e-8x) to give a score between 0 and 1. Obviously, this system will be a lot more lenient for, say, guessing countries in Europe as opposed to guessing countries in Africa, but I had to make a compromise.
A - Eat shit. B - The UN recognizes 193 countries as, well, countries, but the only internationally recognized system that uniformly assigns an identifier to each "country" is the ISO 3166 standard, which lists 249 designated territories. This, however, includes dependant territories, and the quiz is hard enough without them, so I pruned a lot of em out. You can view the entire list, and more details here.
You wasted however many minutes doing something completely pointless!
Any questions?